BAGHDAD, Iraq – Sunni Arab and secular Shiite factions demanded Thursday that an international body review complaints about voting fraud in last week’s elections and threatened to boycott the new legislature. But the United Nations rejected the idea.

“The U.N. is not going to conduct an independent review of the election results,” U.N. associate spokesman Robert Sullivan said in New York.

The demand for a review came two days after preliminary returns indicated the current governing group, the Shiite religiously oriented United Iraqi Alliance, was getting bigger than expected majorities in Baghdad, which has large numbers of Shiites and Sunnis.

Although final results are not expected until January, secular Shiites and Sunni Arabs were alarmed. The formerly dominant Sunni minority, in particular, fears being marginalized by the Shiite majority, which was oppressed during Saddam Hussein’s reign.

But the criticisms of the election could also be part of jockeying for position by both Sunnis and former Prime Minister Ayad Allawi, a secular Shiite, before negotiations begin on forming a new coalition government. No group is expected to win a majority of the legislature’s 275 seats.

A representative for Allawi described the Dec. 15 vote as “fraudulent” and called the elected lawmakers “illegitimate.”

Thirty-five political groups that competed in the vote issued a statement calling for the disbandment of the electoral commission, known as the IECI, because of alleged problems with the balloting.

The groups said the hundreds of complaints about fraud and intimidation of voters should be reviewed by international organizations such as the United Nations, the European Union, the Organization of the Islamic Conference or the Arab League.

“We hold the IECI responsible for all the violations which took place during the elections and demand that it be dissolved and a suitable alternative to be found,” said the statement, read by Ali al-Timimi, head of a secular Shiite candidate grouping, the Hilla al-Fayha List.

He added that “if this is not achieved, then we will have no choice but to refuse the results and boycott the new parliament.”

Jalal Talabani, the country’s Kurdish president, met with representatives of the main Sunni Arab coalition, the Iraqi Accordance Front, in an effort to defuse the crisis.

“There is a dangerous situation after the release of the preliminary results of the elections, and we are working to avoid any political crisis,” said Planning Minister Barham Saleh, a member of Talabani’s Patriotic Union of Kurdistan.

He added that all of Iraq’s political parties “have to deal with the electoral commission positively to find a solution to this problem.”

Asked whether he was pressing for an independent United Nations review, Iraq’s U.N. ambassador, Samir Sumaidaie, said he was not, and would not “unless I’m instructed to push for it” by the interim government.

“The election law in Iraq has a provision for review. There is a tribunal. The independent commission has clear procedures in the case of complaints – and there are some complaints – of how to pursue them. So this procedure should be followed,” he said.

In Washington, State Department spokesman Sean McCormack said the Independent Electoral Commission of Iraq has “a good record of working through these allegations of irregularities and doing so in a manner that meets international standards.”

In the election dispute, the electoral commission said it had received more than 1,500 allegations of voting violations, describing 25 of them as serious. But it said it did not expect the complaints to change the results.

A senior member of the Shiites’ United Iraqi Alliance urged politicians to accept the results.

“These statements will lead the country to new chaos,” Ali al-Adib said of the threatened boycott. “Who can guarantee that when the elections are rerun they will not reject them again?

“They have to accept the will of the Iraqi people, the will of the majority,” al-Adib added. “The political process will continue even if they boycott it.”

Most estimates say Sunni Arabs make up about 20 percent of the population, although many in the minority insist they comprise 40 percent of Iraq’s 27 million people. Shiites are estimated to make up 60 percent of the population, while Kurds account for 20 percent.

Sunni Arabs have lost their dominant position for the first time in hundreds of years in Baghdad – long the heart of regional Sunni Arab culture and education. The group dominated politics and government long before Saddam, himself a Sunni Arab, seized power in the 1970s.

It took nearly three months to put together the interim government after the Jan. 30 election, which gave the Shiites 140 seats, the Kurds 75, Allawi 40 and Sunni Arabs 17.

Politicians say the Shiite religious alliance seems on course to win between 120 and 130 seats this time. Sunni Arabs may increase their seats to more than 40, while the Kurds are expected to get between 40 and 50. Allawi is seen as the big loser, dropping below 20 seats.